It is known from the prior art that plastics mouldings can be bonded to one another via welding. The thermoplastics are heated locally to an adequately high temperature, and are joined at the heated sites. The heating takes place in the context of ultrasound jointing, vibration welding or, for example, laser welding. Techniques of this type are used by way of example by the company Branson Ultraschall in Dietzenbach, Germany.
A process known from the prior art begins, if necessary, by subjecting a fibre-reinforced sheet-type starting material to a forming process. As can be found by way of example in the publication by Sonja Pongratz and Hans Laich “Es muss nicht immer Stahl sein” [It does not always have to be steel], in Kunststoffe July 2004, plastics material is applied by injection, in an injection mould, onto the starting material after it has been subjected to the forming process. Fibre-reinforced sheet-type starting material for the purposes of the present invention is commercially available, for example from the company Bond—Laminates GmbH in Brillon in Germany.
The fibres are composed by way of example of glass, carbon or aramid. The material also encompasses thermoplastics or thermosets. Thermoplastics used comprise PA, PBT, TPU, PC or PPS, as published in November 2005 by way of the Internet on the www.bond-laminates.com page. This Internet page also reveals that the starting material can be used for production of mouldings via a forming process and/or attachment of bonding elements and of reinforcing elements via welding or injection moulding.
If plastics material is applied by injection to a sheet-type starting material, the bonds that result between the sheet-type starting material and the plastics material applied by injection are of relatively low mechanical stability.
It is an object of the invention, in an injection-moulding process, to improve the bond between a fibre-reinforced starting material and a material applied thereto.